package com.ah.hf.controller;

import com.ah.hf.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

@RestController
@RequestMapping("/common")
@Slf4j
public class CommonController {

    @Value("${reggie.path}")
    private String basePath;

    //文件上传
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        log.info("file : {}",file);

        //原始文件名
        String originalFilename = file.getOriginalFilename();
        //截取到 .jpg 后缀名拼接到文件名后面
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));

        //使用uuid生成文件名，防止文件名重复
        String fileName = UUID.randomUUID().toString() + suffix;

        File dir = new File(basePath);

        //如果不存在，就创建该目录
        if (!dir.exists()){
            dir.mkdirs();
        }

        try {
            //将临时文件存到指定位置
            file.transferTo(new File(basePath+fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return R.success(fileName);
    }


    //文件下载
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        FileInputStream fileInputStream = null;

        ServletOutputStream out = null;

        response.setContentType("image/jpeg");
        try {
            //输入流，读取文件内容
            fileInputStream = new FileInputStream
                    (new File(basePath + name));
            //输出流，将文件写回浏览器
             out = response.getOutputStream();

            //定义一个长度为零的
            int len = 0;
            //一次读1024长度的数据
            byte[] bytes = new byte[1024];

            //没有写完一直写
            while((len = fileInputStream.read(bytes)) != -1){
                //每次写给浏览器的数据
                out.write(bytes,0,len);
                //刷新流
                out.flush();
            }

        }  catch (IOException e) {
            e.printStackTrace();
        }
        //关闭流
        finally{
            try {
                fileInputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                out.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

}
